"The behavior is unacceptable for people working in a restaurant," Taco Bell said in a statement at the time. "Our franchisee is responsible for the employment and conduct of his restaurant's employees and he has informed us that he immediately suspended the employee shown in the photo and is in the process of terminating his employment."

Laura Ries, a brand consultant, told the USA Today that it's very difficult for fast-food chains to stop this kind of behavior from happening. The best they can do is train staff on the possible health and safety risks as well as possible public relations damage by such actions.

"Fast-food companies will never be able to totally prevent this kind of thing," Ries said. "The majority of their workers are young adults armed with cellphones and getting paid minimum wage. It is the nature of the beast."